diff --git a/app/vminsert/common/streamaggr.go b/app/vminsert/common/streamaggr.go
index 6a512c81c..d45cf86d8 100644
--- a/app/vminsert/common/streamaggr.go
+++ b/app/vminsert/common/streamaggr.go
@@ -174,6 +174,7 @@ func pushAggregateSeries(tss []prompbmarshal.TimeSeries) {
 	ctx.skipStreamAggr = true
 	for _, ts := range tss {
 		labels := ts.Labels
+		ctx.Labels = ctx.Labels[:0]
 		for _, label := range labels {
 			name := label.Name
 			if name == "__name__" {
diff --git a/docs/CHANGELOG.md b/docs/CHANGELOG.md
index f81a128cd..51a3c01f6 100644
--- a/docs/CHANGELOG.md
+++ b/docs/CHANGELOG.md
@@ -65,6 +65,7 @@ The following tip changes can be tested by building VictoriaMetrics components f
 * BUGFIX: [alerts-health](https://github.com/VictoriaMetrics/VictoriaMetrics/blob/master/deployment/docker/alerts-health.yml): update threshold for `TooHighMemoryUsage` alert from 90% to 80%, since 90% is too high for production environments.
 * BUGFIX: [vmbackup](https://docs.victoriametrics.com/vmbackup.html): fix compatibility with Windows OS. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/70).
 * BUGFIX: [vmctl](https://docs.victoriametrics.com/vmctl.html): fix performance issue when migrating data from VictoriaMetrics according to [these docs](https://docs.victoriametrics.com/vmctl.html#migrating-data-from-victoriametrics). Add the ability to speed up the data migration via `--vm-native-disable-retries` command-line flag. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/4092).
+* BUGFIX: [stream aggregation](https://docs.victoriametrics.com/stream-aggregation.html): fix bug with duplicated labels during stream aggregation via single-node VictoriaMetrics. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/4277).
 
 ## [v1.90.0](https://github.com/VictoriaMetrics/VictoriaMetrics/releases/tag/v1.90.0)